Refrigerator door control



y. G. sHARPE REFRIGERATOR DooR CONTROL July 7, 1959 2 Sheets-Sh eet 1Filed July 19, 1956 JNVENToR. Ver/as 6. Sharpe BY Hfs Aorney July 7,1959 v. G. sHARPE REFRIGERATOR DOOR CONTROL 2 Sheets-Sheet 2 Filed July19. 1956 F ig. 7

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Ver/os 6. Sharpe Y B x? H/'s Attorney United States atcnt O 2,393,726REFRrGERAroR Doon coN'rnoL Verlos G. Sharpe, Dayton, `Ohio, assignor toG eneral Motors Corporation, Detroit, Mich., a corporation of DelawareApplication July 19, 1956, Serial No. 598,877

1 Claim. (Cl. 268-72) This invention relates to a domestic appliance andmore particularly to a door actuating mechanism for a refrigerator.

An object of the invention is to provide means for opening arefrigerator door in response to the closing of an electrical switchlocated without the interior of the refrigerator cabinet.

Another object is to provide means for opening a refrigerator door inresponse to the bridging of a pair of metallic parts located without therefrigerator cabinet with an electrical resistance having a relativelyhigh value.

A more specific object is to provide a refrigerator with friction catchmeans for lholding the refrigerator door closed, and with a solenoidconnected between the door and refrigerator cabinet for opening the dooragainst the bias of the friction catch means, the solenoid beingconnectable with a voltage supply by a switch located without theinterior of -the refrigerator cabinet.

Further objects and advantages of the present invention will be apparentfrom the following description, reference being had to the accompanyingdrawings, wherein a preferred form of the vpresent invention is clearlyshown.

In the drawings:

Figure 1 is 'a side view of a refrigerator showing the electricalconnections for the door actuating means of this invention and showingthe friction catch means for the refrigerator door;

Figure 2 is a front view of a refrigerator with the refrigerator dooropen, showing the electrical connections for actuating the door openingmeans of this invention;

Figure 3 is an enlarged side view of a switch that is used to connect adoor actuating solenoid of this invention with a voltage supply, theswitch being in the open position; y

Figure 4 is an enlarged side view of the switch of Figure 3 with theswitch shown in the closed position;

Figure 5 is an enlarged sectional view taken along line 55 of Figure l;

Figure 6 is a front view of a refrigerator having a modified controlcircuit for the door opening mechanism;

Figure 7 is a sectional view taken along line 7 7 of Figure 6; and

Figure 8 is a schematic electrical illustration of a switch actuatingcircuit used in the modified door opening arrangement of Figure 6.

Referring now to Fig. l, a refrigerator having a cabinet generallydenoted by reference numeral 10 is shown provided with a door 12. Thedoor is held in a closed position by means of friction catch or detentmeans generally denoted Iby reference numeral 14. The friction catch ordetent means may include a spring-biased plunger 16 having a roller 18that cooperates with a detent plate 20. The detent plate 20 is recessedas shown, the recess cooperating with roller 18 to hold the door insealing engagement with the cabinet 10 when the door is in a closedposition. A sealing strip 22 of rubber or other Tfice l suitablematerial may be provided between the refrigerator cabinet 10 and door 12to insure an air-tight tit therebetween. The door 12 carries anelectrical switch generally denoted by reference numeral 24. Theelectrical switch 24 is connected in series with a solenoid generallydenoted by reference numeral 26. The solenoid 26 and electrical switch24 are connected to electrical lines 28 that are in turn connected to aconventional llO-volt voltage supply by means of suitable leads and an`electrical plug connector (not shown).

The solenoid 26, as more particularly shown in Fig. 5, comprises aplunger 29 that slides Within a solenoid winding 30. The solenoidplunger 29 is spring-biased to a retracted position by means of a-spring 32 interposed between spring retainer 34 and a plunger abutment36.

`The solenoid plunger is reduced as at 38 and has a shoulder 40 thatcooperates with a shoulder 42 formed on solenoid frame 44 to limitoutward movement of plunger 29. With this arrangement the solenoidplunger is normally held in a retracted position. When switch 24 isclosed so as to energize the winding 30, the plunger 29 moves leftwardlyin Fig. 5 to open the door 12 of the refrigerator against the bias offriction catch device 14. The opening force of the solenoid ispreferably of a value just strong enough to overcome the spring bias ofthe friction catch device 14.

The switch 24 is preferably mounted within the door 12 of therefrigerator so lthat the actuating touch plate 54 of the switch issubstantially ush with the outer wall of door 12. As more particularlyshown in Figs. 3 and 4, the switch 24 comprises a main base portion 46having anged portions to which is attached an insulating block 48. Theinsulating lblock 48 carries a conventional overcenter spring-typeswitch structure that includes a contact bar 50 that engages a contact52 when the switch is in a closed position. The switch is'shown in theopen position in Fig. 3 and in the closed position in Fig. 4.v

The switch 24 is actuated by a touch plate 54 that extendslongitudinally of the switch. The touch plate is secured to the flangedportion of the main base portion 46 and is spring biased away from thebase portion by means of springs 56. With this arrangement any leftwardpressure on touch plate 54 at any point along the length of the touchplate will actuate the switch 24 to move the contactor 50 to theposition shown in Fig. 4. When this happens, the solenoid 26 isenergized and kicks the door open.

A modified arrangement for energizing a solenoid for opening arefrigerator door is illustrated in Figs. 6, 7 and 8. In thisarrangement the solenoid is energized in response to the bridging of apair of metallic parts with a high resistance. The two metallic partsare preferably secured to the refrigerator at some point without theinterior of the refrigerator cabinet. The two metallic parts may bearranged as shown in Figs. 6 and 7 wherein an inner metal strip 58 ispreferably secured to the outer face of refrigerator door 12 and extendslaterally thereacross. A second metallic strip 60 is secured to therefrigerator door 12 and extends laterally across the front face of therefrigerator door. The metallic strips 58 and 60 are separated by anelectrical insulator 62 that extends coextensively with the metallicstrips 58 and 60. The metallic strips 58 and 60 could be used as thedecorative trim strip material for the door of the refrigerator.

The metallic strips 58 and 60 are connected with a switch-boxarrangement 64 by means of leads 66 and 68. The switch-box 64 containsmechanism that operates to complete a circuit to solenoid 26 when themetallic strips 58 and 60 are bridged with an electrical resistance of arelatively high value. This bridging may take place by the user of therefrigerator bridging the plates 3 58 and 60 by touching the plates withthe human hand or the like.

The switchbox 64 is shown in Fig. 6 and as shown schematically in Fig.8, is connected with conventional power lines L1 and L2 by means ofleads 70 and 72. The solenoid 26 is connected with line L1 by means of alead 74 and is connected to the switch box mechanism by means of a lead76. The switch-box is connected with line L2 by means of a lead 78 thatis connected with a terminal post 80. The electrical line 76 isconnected with a second terminal point 82, the terminal points 80 and 82being bridged at times by a switch S4. With this arrangement the leads70 and 72 supply power to the switching arrangement contained inswitch-box 64 while the leads 76 and 78 are bridged at times by switch84 to complete a circuit for solenoid 26.

The switch-box 64 contains the mechanism shown schematically in Fig. 8.Thus, the line 70 is connected with a resistor R1 and with a dry diskrectiler 86. The line 70 is also connected through a resistor R2 withelectric leads 68 that is connected with metal strip 58. The electricalline 72 is connected with a relay 88 that operates to close switch 84Awhen the relay is energized. A condenser 90 is connected across lines70 and 72 and is connected in parallel with a cold cathode gas tube 92having a plate 94 and a firing electrode 96. The tiring electrode isconnected with a lead 66 through a resistor R3. With this circuitarrangement the bridging or shorting of metallic plates 58 and 60` witha high resistance, places a relatively high resistance across lines 66and 68. The insertion of a relatively high resistance between leads 66and 68 raises the potential of the tiring electrode 96 toward that ofanode 94, thus causing the tube to lire and causing the condenser 90 todischarge through the gas tube 92. The discharge of condenser 90 causescurrent to ow through relay 88 to temporarily close switch 84 during theperiod in which current is owing through relay 88. Closing of switch 84in response to the energization of relay 88 makes a circuit for solenoid26 through lines 74 and 78 thereby energizing solenoid 26 to open door12 against the spring bias of latch mechanism 14.

It will be apparent from the foregoing that all that is needed to openthe refrigerator door with the arrangement shown in Figs. 6, 7 and `8 isa touching by the user of the metallic plates 58 and 60. It is alsoapparent that the circuit arrangement shown in Fig. 8 might take variousforms as long as the circuit responds to the bridging or shorting of themetal plates S8 and 60 with an electrical resistance of a relativelyhigh value.

While the form of embodiment of the invention as herein disclosedconstitutes a preferred form, it is to be to be understood that otherforms might be adopted, as may come `within the scope of the claim whichfollows.

What is claimed is as follows:

A refrigerator comprising, a cabinet having an opening, a `door providedwith an elastic door seal about' its periphery arranged to engage thefront of said cabinet for closing said opening, yieldable holding meansassociated with said door and cabinet for yieldably holding said door inengagement with said cabinet and for compressing said door seal whensaid door is in a closed position, a solenoid having a movable actuatingpart associrated with said door and cabinet, said solenoid operatingwhen energized to overcome said yieldable holding means and to move saiddoor toward an open position thereby releasing said holding means, theelastic compression of said door seal assisting said solenoid in theopening of said door, and switch means for connecting said solenoid witha voltage supply, said switch means inc1uding a pair of metal partslocated without the interior of said cabinet and actuating meansactuated by the bridging of said metal parts with a resistance having arelatively high value.

References Cited in the ille of this patent UNITED STATES PATENTS647,061 Woodcock Apr. 10, 1900 725,552 Gerald Apr. 14, 1903 1,089,963Reinert Mar. 10, 1914 2,096,902 Lamb Oct. 26', 1937 2,186,825 Dome Jan.9, 1940 2,601,983 Schoelkopf July 1, 1952

